Appendix B - Action and Limit Levels

 

Table B-1       Action and Limit Levels for 1-hour TSP

Monitoring station

Action Level (ug/m3)

Limit Level (ug/m3)

KTN-DMS4

297

500

 

 

 

 

Table B-2       Action and Limit Levels for 24-hour TSP

Monitoring station

Action Level (ug/m3)

Limit Level (ug/m3)

KTN-DMS4

192

260

 

 

 

 

Table B-3       Action and Limit Levels for Construction Noise

Time Period

Action Level

Limit Level

0700-1900 hrs on normal weekdays

When one documented complaint is received

75 dB(A) *

 

 

 

 

 

 

Noted:

If works are to be carried during restricted hours, the conditions stipulated in the construction noise permit issued by the Noise Control Authority have to be followed.

(*)           reduce to 70 dB(A) for schools and 65 dB(A) during school examination periods.

 

Table B-4.1    Action and Limit Levels for Water Quality Monitoring(1)

Parameters

Action Level

Limit Level

DO in mg/L (depth average)#+

5 percentile of baseline data.

4 mg/L or 1 percentile of baseline data.

SS in mg/L (depth averaged)*&

95 percentile of baseline data or 120% of upstream control station.

20 mg/L or 99 percentile of baseline data or 130% of upstream control station.

Turbidity in NTU (depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

Unionized ammonia in mg/L

(depth averaged)*~

95 percentile of baseline data or 120% of upstream control station.

0.021mg/L or 99 percentile of baseline data or 130% of upstream control station.

Nitrate nitrogen in mg/L

(depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

Orthophosphate in mg/L (depth averaged)*^

95 percentile of baseline data or 120% of upstream control station.

99 percentile of baseline data or 130% of upstream control station.

 

Remarks:

# AL of DO is 5 percentile of baseline data or level at control station at same tide of the same day (whichever lower) and LL of DO is 4.0 mg/L or level at control station at same tide of the same day (whichever lower);

+ 1 percentile of baseline data were adopted for LL for DO as those levels were greater than 4 mg/L;

* AL is 120% of control station¡¦s level at the same tide of the same day when depth average greater than 95 percentile of baseline data;

^ LL is 130% of control station¡¦s level at the same tide of the same day when depth average greater than 99 percentile of baseline data.

~ LL is 130% of control station¡¦s level at the same tide of the same day when depth average greater than 99 percentile of baseline data or 0.021mg/L.

& LL is 130% of control station¡¦s level at the same tide of the same day when depth average greater than 99 percentile of baseline data or 20mg/L.

 

Table B-4.2    Summary of Baseline Water Quality Monitoring Results (KTN NDA)(1)

Monitoring Parameter

                       Location

 

 

Parameter

KTN-CS1

Max

Min

Average

5 Percentile

1 Percentile

DO in mg/L

7.79

6.28

6.82

6.32

6.28

 

Max

Min

Average

95 Percentile

99 Percentile

Turbidity in NTU

72.4

4.59

10.88

62.2

72.2

Suspended Solid in mg/L

74

2

9

60

73

Unionized ammonia in mg/L

0.0005

0.0001

0.0003

0.0004

0.0005

Nitrate nitrogen in mg/L

0.52

0.09

0.27

0.50

0.52

Orthophosphate in mg/L

0.19

0.01

0.10

0.17

0.19

 

Monitoring Parameter

                       Location

 

 

Parameter

KTN-IS1

Max

Min

Average

5 Percentile

1 Percentile

DO in mg/L

8.08

4.71

6.83

6.14

5.02

 

Max

Min

Average

95 Percentile

99 Percentile

Turbidity in NTU

44.56

4.57

8.63

38.98

44.56

Suspended Solid in mg/L

35

2

6

31

35

Unionized ammonia in mg/L

0.0006

0.0001

0.0004

0.0005

0.0006

Nitrate nitrogen in mg/L

0.57

0.09

0.29

0.54

0.57

Orthophosphate in mg/L

0.14

0.03

0.09

0.13

0.14

 

Note:

(1) The Action and Limit Levels for Water Quality Monitoring and the Summary of Baseline Water Quality Monitoring Results are according to pre-construction ET¡¦s Updated EM&A Manual and Baseline Water Quality Monitoring Report (KTN & FLN NDA).

 

Table B-5       Action and Limit Levels for Ambient Arsenic Monitoring

Parameter

Action Level

Limit Level

Ambient Arsenic Concentration

9.36ng/m3

- 80% of 11.7ng/m3 ¡V the highest ambient arsenic concentration predicted during the construction phase with mitigation measures implemented)

11.7ng/m3

- the highest ambient arsenic concentration predicted during the construction phase with mitigation measures implemented

 

 

 

 

 

 

 

Table B-6       Action level in the event of LFG being detected

 Parameter

Monitoring Results

Actions

O2

<19% v/v

Increase underground ventilation to restore O2 to >19% v/v

<18% v/v

Stop works, evacuate all personnel, prohibit entry, and increase ventilation to restore O2 level to >19%

CH4

>10% LEL

Prohibit hot works, increase ventilation to restore CH4 to <10% LEL

>20% LEL

Stop works, evacuate all personnel, increase ventilation further to restore CH4 to <10% LEL

CO2

>0.5% v/v

Increase ventilation to restore C O2 to <0.5% v/v

>1.5% v/v

Stop works, evacuate all personnel, increase ventilation further to restore CO2 to <0.5%